npm start fails on a fresh clone: @translations/i18next cannot be resolved by webpack

Package version (if known): master (v3.2.0)

## Describe the bug
`npm start` fails to compile on a fresh clone. Ten components that import
`@translations/i18next` fail with:

Module not found: Error: Can't resolve '@translations/i18next'

Affected: AutocompleteSearchBar, EmptyResults, Error, RangeCustomFilter,
RangeFacet, ResultsPerPage, SearchBar, SortBy, SortOrder, Sort.

The `@translations/i18next` alias is defined for Jest (`jest.moduleNameMapper`
in package.json) and for the library build (`@rollup/plugin-alias` in
rollup.config.js), but nothing provides it to webpack, which is what
`react-scripts start` uses. So tests and `npm run build` pass while only the
demo dev server is broken, which may be why this hasn't surfaced.

I confirmed the cause by adding a local shim in node_modules mapping the alias
to `src/lib/i18next`. After that `npm start` compiles and the demos render.

## Steps to Reproduce
1. git clone https://github.com/inveniosoftware/react-searchkit.git
2. npm install
3. npm start

## Expected behavior
`npm start` compiles and serves the demo apps.

## Additional context
Node 24.11.1, Windows 11.

CRA doesn't allow custom webpack aliases without ejecting, so the fix likely
needs a maintainer decision (relative import in the demos, or a
jsconfig/craco setup). Happy to open a PR once there's a preferred direction.

Reproduce the failure with npm start, then compare the @translations/i18next mappings in package.json and rollup.config.js with the webpack path used by react-scripts. Review the affected components and src/lib/i18next before choosing between the relative-import and CRA configuration directions. Done means the demo apps compile and render from a fresh clone.

Written by the indexing model from the issue text.